Bug 1534160 - Part 2: Cherry-pick patch for Android time zone detection. r=jwalden

Cherry-pick the commit from <https://github.com/unicode-org/icu/pull/605>.

Depends on D82545

Differential Revision: https://phabricator.services.mozilla.com/D82546

intl/icu-patches/bug-1534160-android-timezone.diff

@@ -0,0 +1,112 @@
+commit 6099f062f5d0e79586149d9a8963525a59f89557
+Author: Makoto Kato <m_kato@ga2.so-net.ne.jp>
+Date:   Fri Nov 22 16:51:30 2019 +0900
+
+    ICU-11992 uprv_tzname doesn't return valid time zone on Android
+
+# ICU bug report:
+# https://unicode-org.atlassian.net/browse/ICU-11992
+#
+# Pull request:
+# https://github.com/unicode-org/icu/pull/605
+#
+# Commit:
+# https://github.com/unicode-org/icu/commit/c9037ca8d3c0738f1a044dd845bdc0dc646f3e97.patch
+
+diff --git a/intl/icu/source/common/putil.cpp b/intl/icu/source/common/putil.cpp
+--- a/intl/icu/source/common/putil.cpp
++++ b/intl/icu/source/common/putil.cpp
+@@ -116,15 +116,19 @@
+ #   include <unistd.h>
+ #   if U_PLATFORM == U_PF_SOLARIS
+ #       ifndef _XPG4_2
+ #           define _XPG4_2
+ #       endif
++#   elif U_PLATFORM == U_PF_ANDROID
++#       include <sys/system_properties.h>
++#       include <dlfcn.h>
+ #   endif
+ #elif U_PLATFORM == U_PF_QNX
+ #   include <sys/neutrino.h>
+ #endif
+ 
++
+ /*
+  * Only include langinfo.h if we have a way to get the codeset. If we later
+  * depend on more feature, we can test on U_HAVE_NL_LANGINFO.
+  *
+  */
+@@ -1041,13 +1045,57 @@ static char* searchForTZFile(const char* path, DefaultTZInfo* tzInfo) {
+     }
+     return result;
+ }
+ #endif
+ 
++#if U_PLATFORM == U_PF_ANDROID
++typedef int(system_property_read_callback)(const prop_info* info,
++                                           void (*callback)(void* cookie,
++                                                            const char* name,
++                                                            const char* value,
++                                                            uint32_t serial),
++                                           void* cookie);
++typedef int(system_property_get)(const char*, char*);
++
++static char gAndroidTimeZone[PROP_VALUE_MAX] = { '\0' };
++
++static void u_property_read(void* cookie, const char* name, const char* value,
++                            uint32_t serial) {
++    uprv_strcpy((char* )cookie, value);
++}
++#endif
++
+ U_CAPI void U_EXPORT2
+ uprv_tzname_clear_cache()
+ {
++#if U_PLATFORM == U_PF_ANDROID
++    /* Android's timezone is stored in system property. */
++    gAndroidTimeZone[0] = '\0';
++    void* libc = dlopen("libc.so", RTLD_NOLOAD);
++    if (libc) {
++        /* Android API 26+ has new API to get system property and old API
++         * (__system_property_get) is deprecated */
++        system_property_read_callback* property_read_callback =
++            (system_property_read_callback*)dlsym(
++                libc, "__system_property_read_callback");
++        if (property_read_callback) {
++            const prop_info* info =
++                __system_property_find("persist.sys.timezone");
++            if (info) {
++                property_read_callback(info, &u_property_read, gAndroidTimeZone);
++            }
++        } else {
++            system_property_get* property_get =
++                (system_property_get*)dlsym(libc, "__system_property_get");
++            if (property_get) {
++                property_get("persist.sys.timezone", gAndroidTimeZone);
++            }
++        }
++        dlclose(libc);
++    }
++#endif
++
+ #if defined(CHECK_LOCALTIME_LINK) && !defined(DEBUG_SKIP_LOCALTIME_LINK)
+     gTimeZoneBufferPtr = NULL;
+ #endif
+ }
+ 
+@@ -1082,11 +1130,15 @@ uprv_tzname(int n)
+     }
+ #endif*/
+ 
+ /* This code can be temporarily disabled to test tzname resolution later on. */
+ #ifndef DEBUG_TZNAME
++#if U_PLATFORM == U_PF_ANDROID
++    tzid = gAndroidTimeZone;
++#else
+     tzid = getenv("TZ");
++#endif
+     if (tzid != NULL && isValidOlsonID(tzid)
+ #if U_PLATFORM == U_PF_SOLARIS
+     /* When TZ equals localtime on Solaris, check the /etc/localtime file. */
+         && uprv_strcmp(tzid, TZ_ENV_CHECK) != 0
+ #endif

intl/icu/source/common/putil.cpp

@@ -118,11 +118,15 @@
 #       ifndef _XPG4_2
 #           define _XPG4_2
 #       endif
+#   elif U_PLATFORM == U_PF_ANDROID
+#       include <sys/system_properties.h>
+#       include <dlfcn.h>
 #   endif
 #elif U_PLATFORM == U_PF_QNX
 #   include <sys/neutrino.h>
 #endif
 
+
 /*
  * Only include langinfo.h if we have a way to get the codeset. If we later
  * depend on more feature, we can test on U_HAVE_NL_LANGINFO.
@@ -1043,9 +1047,53 @@ static char* searchForTZFile(const char* path, DefaultTZInfo* tzInfo) {
 }
 #endif
 
+#if U_PLATFORM == U_PF_ANDROID
+typedef int(system_property_read_callback)(const prop_info* info,
+                                           void (*callback)(void* cookie,
+                                                            const char* name,
+                                                            const char* value,
+                                                            uint32_t serial),
+                                           void* cookie);
+typedef int(system_property_get)(const char*, char*);
+
+static char gAndroidTimeZone[PROP_VALUE_MAX] = { '\0' };
+
+static void u_property_read(void* cookie, const char* name, const char* value,
+                            uint32_t serial) {
+    uprv_strcpy((char* )cookie, value);
+}
+#endif
+
 U_CAPI void U_EXPORT2
 uprv_tzname_clear_cache()
 {
+#if U_PLATFORM == U_PF_ANDROID
+    /* Android's timezone is stored in system property. */
+    gAndroidTimeZone[0] = '\0';
+    void* libc = dlopen("libc.so", RTLD_NOLOAD);
+    if (libc) {
+        /* Android API 26+ has new API to get system property and old API
+         * (__system_property_get) is deprecated */
+        system_property_read_callback* property_read_callback =
+            (system_property_read_callback*)dlsym(
+                libc, "__system_property_read_callback");
+        if (property_read_callback) {
+            const prop_info* info =
+                __system_property_find("persist.sys.timezone");
+            if (info) {
+                property_read_callback(info, &u_property_read, gAndroidTimeZone);
+            }
+        } else {
+            system_property_get* property_get =
+                (system_property_get*)dlsym(libc, "__system_property_get");
+            if (property_get) {
+                property_get("persist.sys.timezone", gAndroidTimeZone);
+            }
+        }
+        dlclose(libc);
+    }
+#endif
+
 #if defined(CHECK_LOCALTIME_LINK) && !defined(DEBUG_SKIP_LOCALTIME_LINK)
     gTimeZoneBufferPtr = NULL;
 #endif
@@ -1084,7 +1132,11 @@ uprv_tzname(int n)
 
 /* This code can be temporarily disabled to test tzname resolution later on. */
 #ifndef DEBUG_TZNAME
+#if U_PLATFORM == U_PF_ANDROID
+    tzid = gAndroidTimeZone;
+#else
     tzid = getenv("TZ");
+#endif
     if (tzid != NULL && isValidOlsonID(tzid)
 #if U_PLATFORM == U_PF_SOLARIS
     /* When TZ equals localtime on Solaris, check the /etc/localtime file. */

intl/update-icu.sh

@@ -58,6 +58,7 @@ for patch in \
  bug-1636984-alias-append-items-sink.diff \
  bug-1636984-display-name-fractional-seconds.diff \
  bug-1636984-append-item-dayperiod-fractional-seconds.diff \
+ bug-1534160-android-timezone.diff \
 ; do
   echo "Applying local patch $patch"
   patch -d ${icu_dir}/../../ -p1 --no-backup-if-mismatch < ${icu_dir}/../icu-patches/$patch